Bad signs or what?

I finally got around to putting a 2nd Gen back seat in my 1st Gen K5, along with some cheap Pep Boy's lap belts. The previous owner had already drilled holes for the front feet, so I used them.

Anyway, during my disastrous trip this past Sunday, I finally had 4 adults in the vehicle at one time. I noticed the powertrain "grab" a couple of times from a dead start on pavement. Almost like drum brakes still not released, but noticeable or if I had a locked rear diff on dry pavement (it is the factory limited slip). What should I be looking for? Here are some other factors:
(1) daily driver (90 miles a day - ouch) at 80-85 mph almost all the way
(2) GM Goodwrench 350 w/QJet, new X-Flo filter assy from K&amp;N
(3) TH350 (original)
(4) NP205 that leaks (was bone dry before this excursion, I added synthetic oil to the correct amount before heading out)
(5) Corp 12 bolt limited slip in the rear
(6) 33" BFG's
(7) no lifts or other mods

It seemed to run fine on the highway. I couldn't tell if I was feeling more vibrations cause of the additional weight or not. When I was towed out by the Jeep, it rolls smooth as silk with all four guys and tranny/t-case in neutral. Thanks for any help.

this is a way out there possibility, with the 4 adults, could it have stretched ur ebrake cable to cause them to grab slightly when you gave it gas? all the extra weight shifting to the rear pullin the ebrake slightly, but once going the weight redistributing and releasing them? Possible?

Useful Searches

>
About Us>
>
In May of 1999 CK5 started out as a tribute to America's favorite 4x4 utility truck. Since then it has grown to be
a leader among full size Chevrolet K5 Blazer and GMC Jimmy web sites across the Internet. CK5 has since expanded
to include the C/K series GM Truck and Suburban as well as past and present GM models.
>>
With its technical articles, factory specifications, photo gallery, classifieds, active message forum, product
reviews and original automotive content it's an unbeatable source.